1. Field of the Disclosure
The present disclosure relates to a stereoscopic image display device, and more particularly, to a stereoscopic image display device which has a thin thickness and an enhanced aesthetic appearance.
2. Discussion of the Related Art
Generally, stereoscopic images that represent three-dimensionality are realized based on the stereo visual principle of binocular parallax, and the binocular parallax caused by the distance between two eyes is a key factor for three-dimensionality. That is, when left and right eyes watch different Two-Dimensional (2D) images and the different 2D images are delivered to the brain through the retina, the brain will merge the 2D images to reproduce a deep sense and realistic sense of the original Three-Dimensional (3D) image. Such a function is generally referred to as stereography, and a display device based on the stereography is called a stereoscopic image display device.
Such stereoscopic image display devices are classified into active (liquid crystal shutter) type display devices in which a left-eye image and a right-eye image are temporally divided to realize a 3D image, and retarder (polarized glasses) type display devices in which a left-eye image and a right-eye image are spatially divided to realize a 3D image.
A stereoscopic image display device comprising a display panel and a 3D panel to which both the active type and the retarder type are applied in combination, has been proposed recently.
FIG. 1 is a sectional view schematically illustrating a related art stereoscopic image display device.
Referring to FIG. 1, the related art stereoscopic image display device includes an image display panel 10, a display panel driver 20, a front case 30, a 3D optical panel 40, an optical panel driver 50, and a front set cover 60.
The image display panel 10 displays a 2D image or a stereoscopic image according to an image signal applied from the display panel driver 20. Hereinafter, the image display panel 10 will be described on the assumption that a stereoscopic image, namely, a left-eye image and a right-eye image are divided temporally or spatially and displayed. For this end, the image display panel 10 includes a first substrate 12 and a second substrate 14 that face each other and are coupled to each other.
The first substrate 12 includes a plurality of gate lines and data lines that are formed to be intersected and thereby define a plurality of pixel areas, a plurality of thin film transistors that are respectively connected to the gate lines and respectively connected to the data lines, and a plurality of pixel electrodes that are respectively formed in the pixel areas and to be connected to the respective thin film transistors. Further, a display panel pad part is prepared at one side of the first substrate 12 to connect to the gate lines and data lines. A lower polarizing film 12a is adhered to a lower surface of the first substrate 12.
The second substrate 14 is formed to have an area smaller than that of the first substrate 12 such that part of the first substrate 12, namely the display panel pad part, is exposed when the first and the second substrates 12 and 14 are coupled to each other. An upper polarizing film 14a is adhered to an upper surface of the second substrate 14.
The display panel driver 20 is connected to the display panel pad part of the first substrate 12 to supply a gate signal to the gate lines, and supply a left-eye image signal and a right-eye image signal to the data lines in synchronization with the supply of the gate signal.
The front case 30 is provided to cover a peripheral area of the image display panel 10 other than an active area of the image display panel 10. That is, the front case 30 surrounds the peripheral area of the image display panel 10 where the display panel pad part is prepared and the other peripheral areas of the image display panel 10.
The 3D optical panel 40 is configured to divide a left-eye image and a right-eye image, which are displayed on the image display panel 10, to realize a stereoscopic image, in synchronization with the driving of each pixel performed by the display panel driver 20. For this end, the 3D optical panel 40 includes a lower substrate 42 and an upper substrate 44 that are coupled to each other with a liquid crystal layer (not shown) disposed therebetween.
The lower substrate 42 includes a plurality of transparent electrode lines that are formed in correspondence with the respective pixel areas. A 3D panel pad part is prepared at one side of the lower substrate 42 such that an optical panel driver 50 for driving the transparent electrode lines is connected thereto.
The upper substrate 44 includes a transparent electrode layer to overlap with the plurality of first transparent electrode lines.
The optical panel driver 50 is connected to the 3D panel pad part of the lower substrate 42 and applies a plurality of liquid crystal driving signals to the respective transparent electrode lines, and a reference voltage (or common voltage) to the transparent electrode layer.
The 3D optical panel 40 operates the liquid crystal layer for dividing an image according to the liquid crystal driving signals that are respectively applied from the optical panel driver 50 to the transparent electrode lines, and thus divides a left-eye image and a right-eye image that are displayed on the image display panel 10 to realize a stereoscopic image.
The front set cover 60 surrounds both a side of the front case 30 and a front peripheral area of the 3D optical panel 40 other than the area of the 3D optical panel 40 that is overlapped with the active area of the image display panel 10, thereby acting as a set cover of the stereoscopic image display device.
Since the related art stereoscopic image display device includes the front set cover 60 that surrounds the side of the front case 30 and the front peripheral area of the 3D optical panel 40, the thickness and Bezel width of the display device increase due to the front set cover 60, and thus, the aesthetic appearance of the display device is degraded. Also, the aesthetic appearance of the front is degraded due to a step height between the front surface of the front set cover 60 and that of the 3D optical panel 40.